Propeller



' Sept. 6, 1932 G. F. HOUSTON Phorum Filed Nov. 7. 1930 Patented Sept. 6, 1932 4 UNlTEn STATES PATENT. ori-ics GEORGE F. HOUSTON, OF SOUTH BEND, INDIANA., ASSIGNOR TO BENDIX RESEARCH CORPORATION, OF EAST ORANGE, NEW- JERSEY, 'A CORPORATION 0F INDIANA PROPELLEIB.

Application filed November 7, 1930. l Serial No. 484,109.

This invention relates to propellers and vmore particularly to means for mounting propeller blades in a hub.

, It has heretofore been proposed to construct one-piece hubs for. propeller blades, such construction having many and obvious advantages over two-part hubs. In such onepiece hubs it has been usual to attach the propeller blade to the same by means of bolts extending through the hub and blade. However, -the attaching means heretofore employed present certain disadvantages among which may be mentioned the difficulty and manipulation involved in positioning the blade to permit the insertion of the bolts.`

Accordingly, it is one of the objects of the present invention to provide a hub construction for propeller blades which is constituted ,in such a manner as to avoid the above disadvantages.

Another object of this invention is to provide novel means for attaching a propeller blade to a hub, which means shall become oplrative upon insertion of the blade into the Another object is to provide in a propeller construction of thel above character novel means whereby the blade may be easily and quickl detached from the hub.

Stil another object is to provide a novel propeller hub with means whereb a propel- 1er blade may be automatically loclzed therein upon insertion of the blade within the hub.

A further object is to provide a one-piece hub for propeller blades, together with means for attaching the blade to the hub, and means lflorln preventing rotation of the blade in the u A still further object is to provide a vpro-r peller hub construction characterized by a novel arrangement of parts 'resulting in a simple and compact structure and wherein the propeller blades maybe easily and quickly connected and disconnected therefrom.

Other objects and novel features of the invention'will appear more fully hereinafter in the followin detailed description taken in connection with the accompanying drawing. It is to 'bef expressly understood, however,

that `the-.drawing is for purposes of illustration only, and is not designed as a delinition of the limits of the invention, reference being had for this purpose to the appended claims.

In the drawing, wherein like reference Characters refer to like parts throughout the y several views Fig. l is a vertical section of a propeller blade and hub assembly constructed in accordance with the present invention; and

Fig. 2 is a front view of the propeller hub, A construction embodying the present invention isy illustrated as com rising an integrally formed oneiece hu l, having a plurality of sockets 2 or the reception of the inner or root ends of blades and also hav ing a' centrally-disposed openingi:4 to receive a eyed drive .shaft 5 for rotating `the hub.

Means are provided for detachably securing the blade to the hub, and as shown such means comprise annular grooves 6 formed internally of the hub andl opening into the blade-root receiving socket thereof. Al-v though two such annular grooves for each hub-receiving socket are disclosed inthe drawing, it is to be understood that a reater orless number may be satisfactori y employed if desired. Facing these annular grooves or recesses and formed on the propeller root are similar annular recesses 7, the

opposed recesses 6 and 7 forming annular chambers. Means adapted to prevent relative longitudinal movement between the hub and blade aredispo'sed in such annular. charnbers.. 'Such means are constituted b split rings 8 and 9 the abutting ends of which are vresiliently or yieldably held apart by springs 10 in order that the outer peripheries of such rings will be held in firm contact with the annular grooves 6. The rings 8 and 9 are preferably formed with a trapezoidal crosssection, the outer peripheral surface of such rings having portions 11 in contact with the bottoms of the annular grooves 6, and inclined portions 12, as clearly illustrated in V the drawing. The inclination of the inclined portion of the vexterior periphery of ring 9 1s preferably such that when the blade-root is inserted into the hub socket, the expansion `of ring 9 into the outer annular depression 6 tion of the propeller in `fiat portions 11- of the rings 8 and 9.

v ring, as is shown,

in the hub socket will not prevent furtherI insertion of the propeller. To this end the inclination of the inclined peripheral part 12 should extend radially inward of the wall ofthe hub socket when the ring is in its most expanded condition. It isnot necessary that the rings 8 be constructed in this manner but it is desirable that they be so formed in order that the rings may be interchangeable. linstead of accurately machining therinclined portions 12 o the rings 9 to facilitate inser tion oi* the blade into the hub, as described above, such insertion may be eilected yby threading the screws 13, which are opposite the outer groove 6, inwardly of the hub until their innerextremities are substantially lush with the inner wall of the hub socket. With the screws so positioned the rings 9, on insertion of the blade into the socket, cannot exand into the outer groove 6 in order to lock the blade in the hub. On complete insertion of the blade into the socket, however, it will be understood that the screws 13 are moved outwardly again to permit the ring 8 to expand into locking position in the groove 6.

Means are provided for preventing rotathe hub socket, and as shown, such means include an annular groove 14 formed in the outer surface oit the hub and adjacent the outer yextrernidy thereof. Disposed in such groove is a collar 15 having ears 16 'formed on the ends thereof, the same being formed with aligned holes 17 for the reception of a headed bolt 18 which is screw threaded at its end to receive a nut 19. 1n

order to permit such tightening means to contract the hub about the propeller root to frictionally grip the latter, longitudinal slots 20 are formed in the outer extremity of each hub, there being, preferably, two such slots in each hub socket, the same being diametrically opposed. When the propeller'has been inserted in the hub socket the nut 19 is turned to tighten the collar 15 in the groove 14, thereby contracting' the extremity-of the hub socket about the propeller root by real son of the play afforded by the slots 20. y

Means are provided for contracting the split rings 8 and 9, such contraction being necessary in order to effect removal of the blade from the hub. As hereinbefore stated, when the parts are in their assembled position', the rings8 and 9 are expanded outwardly into the recesses 6 by means of the springs 10 which are disposed between their ends. Such rings 8 and 9 must be contracted wholly into thegrooves 7 in order that the blade may be withdrawn from the hub, the means provided for effecting such contraction comprising screws 13 threadedly received in suitable openings provided in the wall othe hub, said screws 13 abuttingTthe wo such screws/are-preferably provided for each but a greater number may '1,875,6oe Y be employed if desired. When it is desired to withdraw the blade romthe socket the screws 13 are turned to move them radially inward of the hub to therebyv abut and contract the rings 8 and 9 against the tension of springs 10.- When such rings are contracted so that their exterior peripheries are entirely interior of the hub socket the blade may be withdrawn -from the socket.

lt will be evident from vthe foregoing description that the present invention provides novel and improved means Yfor attaching a propeller blade to afhub. Such means are' automatically operable on complete insertion of the propeller blade into the hub to prevent relative-longitudinal movement between `the hub and blade, The attaching means is simple in structure and easily operable, it being necessary only to insert the blade into `the hub when the expanding rings have been placed in position on the blade. also been provided for eifecting release of the blade from. the hub, such efficient and .positive in operation. The invention also provides means for preventing rotation of the blade in thehub, such means being operable by a very simple mechanism.

While certain specific 4features of this invention and parts incident thereto have been illustrated and described in detail, it will be apparent that the invention is capable of embodiment in various forms as will now occur to thoseskilled in the art, without departing from the scope of the invention. Reference is therefore to be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. A propeller blade, a hub thereforcomprising a cylindrical member having a plurality of spaced, annular grooves internally thereof, an external. groove at the vfree end of said hub adapted to receive a clamping ring, external annular grooves on said propeller blade adapted to register with the said internal grooves of said hub to form a recess therewith, and spring-actuated expansion rings adapted to be received in said recess to releasably prevent relative movement of said propeller blade and hub.

2. A propeller blade, a hub therefor having internal annular recesses therein, external annular recesses formed on said blade, and yield# ing means disposed within said last-namedv recesses and adapted to be expanded into said first-named recesses to thereby prevent relative longitudinal movement between said hub and said blade; A

3. A propeller blade, a hub therefor. com-- prising a. cylindrical member having a plurality of spaced, annua-lar grooves internally thereof, external annular grooves onl said propeller blade registering with said internal grooves of said hubto formrecesses, and expansiblemeans adapted to be received in said Means have means being simple,

tion of the blade into the hub to attach said-- Vblade to said hub, and means for permitting f ropeller hub having a contractible, andme'ans for electing contraction of said expansible and contractible means' for detaching theA blade from the hub.

In testimony `whereof I have signed this specification.

GEORGE Fi HOUSTON.

release of said blade :from said hub, said lastnamed means being disposed in said hub and cooperating with said first named means.

6. A propeller blade, a hub therefor, means formed in said hub and adapted to coactwith means on said blade for detachably attaching said blade to said hub, and means dis osedin said hub and coacting with said secon -named means to permit detachment of said blade from said hub. y

7. A propeller blade Ahaving annularly-disposed means thereon, a hub for said blade having means formed therein to coact with saidl first-named means, said means on said blade being actuated on complete insertion of said blade into said hub -to attach said blade to -said hub.

8. In a propeller, a blade, a hub, means on the blade for insertion into the hub, andv means automatically actuatedby insertion of the blade into the hub for securing the blade thereto. 9. In a propeller blade and hub construction, the combination with means on the blade for insertion into the hub, of means di p on said first-named means and actuated b complete insertion of saidblade into said hu for attaching said blade thereto.

10. In a device of the class described, apro-l peller blade, a hub, resilient means dis osed fon said blade, andfmeans formed in sai hub to receive said resilient means on complete insertion of said blade in said h ub to thereby attach said blade to said hub.

.11. A propeller blade, a hub hub, said rings being adapted to be received flot` to receive said I blade, expansible and lcontractiblerings on said blade, annular recesses formed in said into said recesses on complete insertion of "said blade into said hub to thereby detachably attach said bladetosaid hub. p

12. A propeller blade, a 1mb to receive said blade, means disposed on saidblade and adapted to coact with means'formed insaid hub to detachably attach said blade to said hub, and screwthreadedlmeans for -permit -ting detachment ofsaid bladeand .said hub.

' 13. In a propeller bladeland hub construction, separate means adapted to coact to rvleasably prevent'detachment of Said blade and hub, one of said means expansible and' ido 

